首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   653篇
  免费   13篇
  2021年   7篇
  2020年   6篇
  2019年   10篇
  2018年   5篇
  2017年   15篇
  2016年   14篇
  2015年   9篇
  2014年   13篇
  2013年   85篇
  2012年   22篇
  2011年   28篇
  2010年   24篇
  2009年   17篇
  2008年   30篇
  2007年   14篇
  2006年   18篇
  2005年   8篇
  2004年   6篇
  2002年   9篇
  2001年   7篇
  1999年   4篇
  1998年   8篇
  1997年   10篇
  1995年   6篇
  1994年   6篇
  1993年   18篇
  1992年   10篇
  1991年   9篇
  1989年   15篇
  1988年   13篇
  1987年   12篇
  1986年   16篇
  1985年   16篇
  1984年   9篇
  1983年   7篇
  1982年   7篇
  1981年   9篇
  1980年   14篇
  1979年   14篇
  1978年   8篇
  1977年   11篇
  1976年   9篇
  1975年   7篇
  1974年   8篇
  1972年   14篇
  1971年   10篇
  1970年   6篇
  1969年   12篇
  1968年   8篇
  1966年   4篇
排序方式: 共有666条查询结果,搜索用时 31 毫秒
471.
472.
Recurrence relations for the product moments of order statistics from a doubly truncated exponential distribution are obtained. These relations allow us to evaluate the product moments for all sample sizes.  相似文献   
473.
This paper analyses the E/M/c queueing system and shows how to calculate the expected number in the system, both at a random epoch and immediately preceding an arrival. These expectations are expressed in terms of certain initial probabilities which are determined by linear equations. The advantages and disadvantages of this method are also discussed.  相似文献   
474.
In this paper we are concerned with several random processes that occur in M/G/1 queues with instantaneous feedback in which the feedback decision process is a Bernoulli process. Queue length processes embedded at various times are studied. It is shown that these do not all have the same asymptotic distribution, and that in general none of the output, input, or feedback processes is renewal. These results have implications in the application of certain decomposition results to queueing networks.  相似文献   
475.
In a static environment, J. Hirschleifer's marginal cost solution to the transfer pricing problem is commonly accepted as analytically correct. However, actual pricing practice within Western corporations and socialist-planned economies generally deviates from marginal cost pricing. Some form of average cost pricing is more commonly chosen. Recently in this journal, H. Enzer has claimed to show that some form of average cost pricing is indeed the analytically correct solution to the transfer pricing problem when choice of technique and manipulation are allowed. Enzer claims that optimal decisions made by each of two divisions according to their individual self-interests are made compatible with overall firm optimization when the transfer price assigned to the internally-transferred commodity is any form of average cost. We show that the marginal cost solution is correct for Enzer's problem in the absence of manipulation by either division. Indeed, this was all that Hirschleifer claimed. In the process, we uncover a fundamental mathematical error in Enzer's argument. When manipulation of the transfer price by divisions is allowed, we demonstrate the faults with Enzer's average cost solution and conclude Hirschleifer's original statements on manipulation to be correct even in Enzer's environment. A final section briefly indicates the importance to the transfer pricing problem of a growing body of economic literature on incentive structures.  相似文献   
476.
The shortest path problem between two specified nodes in a general network possesses the unimodularity property and, therefore, can be solved by efficient labelling algorithms. However, the introduction of an additional linear constraint would, in general, destroy this property and the existing algorithms are not applicable in this case. This paper presents a parametric approach for solving this problem. The algorithm presented would require, on the average, a number of iterations which is polynomially bounded. The similarity of this approach to that of the generalized Lagrange multiplier technique is demonstrated and a numerical example is presented.  相似文献   
477.
A computationally feasible matrix method is presented to find the first-passage probabilities in a Markov chain where a set of states is taboo during transit. This concept has been used to evaluate the reliability of a system whose changes in strength can be thought of as a Markov chain, while the environment in which it is functioning generates stresses which can also be envisaged as another Markov chain.  相似文献   
478.
“Relevation” is the name given by Krakowski to the distribution of failure time of a replacement from an aging stock. The present authors have extended this concept to include (i) hierarchal replacement systems and (ii) dependence between lifetimes of original and replacement items. In this article, we present some further developments, including first steps toward a synthesis of (i) and (ii).  相似文献   
479.
The iteration usually necessary for simultaneous determination of minimum-cost order quantity and reorder point in (Q, r) inventory systems may be eliminated by a graphical technique employing dimensionless ratios. This technique is illustrated for three different types of stock-out penalty.  相似文献   
480.
This article analyzes the political utility of US drone strikes theoretically and deductively. Placing strikes within the context of the theorized political functions of force and considering how they fit into two grand strategies, restraint and selective engagement, I argue that these strikes buy the United States relatively little in the way of political effects assuring its own security because the terrorism threat they are intended to combat is a limited one within the skein of US global interests. Furthermore, their contribution to counter-terrorism efforts is likely to diminish with the adoption of armed drones by non-state actors. Drone strikes can, however, provide leverage over recalcitrant US client states while reassuring liberal partners and giving them some leverage over US choices. In addition, within the counter-terrorism sphere, drone strikes are less likely to inflame popular opinion than are alternative uses of force. This analysis contributes to an increasingly rigorous examination of the strikes’ role in US foreign and security policy.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号